Question

3. Genetic engineering is conducted which alters the neurotransmitter released from a spinal motor interneuron from glycine to glutamate. How would the muscles of the arm respond if the elbow were tapped (similar to the patellar reflex)? Think about the name (flexor / extensor) of the muscle to determine its action

Question options:

A)	The flexors would increase contraction

B)	The flexors would reduce contraction

C)	The extensors would increase contraction

D)	The extensors would reduce contraction

Answer 1

The action of the muscle is conducted in response to neurotransmitters released from the spinal motor neurons. Among the neurotransmitters, glycine acts as inhibitory neurotransmitter, whereas, glutamate acts as exitatory transmitter.

Now, if genetic engineering is conducted, such that the spinal motor interneuron releases glutamate instead of glycine, the muscles will be in a constitutive exitatory mode of action.

As a result of which, (A) The flexors would increase contraction